function createRequest() {
	var client = null;
	try {
		// fei IE liulanqikeyong
		client = new XMLHttpRequest();
	} catch (e) {
	}
	if (client == null) {
		// changshi IE liulanqi
		var namePrefixes = [ "Msxml3", "Msxml2", "Msxml", "Microsoft" ];
		for ( var i = 0; i < namePrefixes.length; i++) {
			var name = namePrefixes[i] + ".XMLHTTP";
			try {
				client = new ActiveXObject(name);
				if (client != null) {
					break;
				}
			} catch (e) {
			}
		}
	}
	return client;
}